If a U.S.-led ban on importing oil from Iran — recently adopted by the European Union — is making officials in Tehran sweat, it’s hard to tell. Iranian President Mahmoud Ahmadinejad claimed Jan. 26 that the West had more to lose from severing trade ties with his country, currently in the crosshairs of international scrutiny because of its controversial nuclear program. Indeed, some analysts predict Iran’s output may even grow this year, buttressed by discount deals it cuts with energy-hungry importers such as China and India.

The case of India, in particular, is worth bearing in mind for Americans. New Delhi’s ties with Washington have grown especially robust in recent years, a consequence both of India’s rise on the global stage as well as the strategic desire on the part of two of the world’s leading democracies to have a closer relationship — not least as authoritarian China poses geopolitical headaches for both. But while U.S. diplomats pressure countries like South Korea and Japan to join the Iran oil ban, they won’t get much joy from their Indian counterparts.

India’s Oil Minister, S. Jaipal Reddy, confirmed that his country had no intention of halting imports from Iran. India draws some 12% of all its foreign crude from Iran, the second biggest exporter to the oil-thirsty Asian giant after Saudi Arabia. Moreover, as international sanctions tighten around corporations doing business with Iran, it appears the Indians and perhaps the Chinese will explore paying the Iranians with gold, the Japanese yen or even in part with their own national currencies. Call it one more episode of the post-American world: considerable regional powers are now attempting to unhinge bilateral trade ties off the U.S. dollar or the euro.

Indian officials, including Reddy, insist that New Delhi will abide by U.N. sanctions authorized by the Security Council, but not other measures taken unilaterally by the U.S. and other Western countries. “We will scrupulously adhere to the sanctions imposed by the U.N. No less, no more,” said Reddy.

Richard Fontaine, a senior adviser at the Center for a New American Security, fears the “collateral damage” of Washington’s Iran gambit “could be the U.S.-India relationship.” He writes in the Diplomat:

With the issue heating up in Washington and other world capitals, and with the new U.S. sanctions poised to go into effect, there’s the danger of a real impasse. Members of the U.S. Congress will be dismayed if India appears to stand outside a concerted international effort to press Iran at a critical inflection point. Members of the Indian parliament, for their part, will not particularly appreciate being publicly goaded to get tough on Iran.

Dating back to the years of the Cold War and the height of the third-worldist Non-Aligned Movement, India has long championed its foreign policy autonomy. Relations warmed under the George W. Bush Administration, and the two sides penned a landmark nuclear-energy deal, but Indian politicians still bristle at the assumption that their country is being drawn into an American orbit.

Indian cultural bonds with Iran are deep — it could be argued that, just a few centuries ago, the main centers of Persian literature and civilization were indeed in what’s now present-day India. These days, Tehran and New Delhi are solidly united in their mutual hatred of the Pakistani-backed Taliban in Afghanistan. A decade ago, they both supported the anti-Taliban rebel Northern Alliance, whose members rose to the fore in Kabul following the 2001 U.S. invasion of Afghanistan. Now India has helped developed the Iranian Arabian Sea port of Chabahar and is constructing roads and highways from the Iranian border into central Afghanistan. It’s a strategic platform that boosts Indian influence in war-torn Afghanistan, something strategists in Washington may want to preserve following the expected U.S. withdrawal in 2014. Indeed, Indian interests in Afghanistan are likely far more in concert with the U.S. than those of Pakistan or China, which has steadily expanded its Afghan footprint as well. The continued escalation of tensions in the Persian Gulf, though, may reset a number of geopolitical calculations, an unwelcome event in a part of the world that has no need for more quagmires.